Position an image depending on its size - javascript

JSFiddle Demo
For the above JSFiddle demo, I need to position the last image so that it is centered, compared to the first three images.
How do I do this?
position()
window.onresize = function(event) {
position();
};
function position(){
var id = document.getElementById( "imageDisplay" );
console.log( window.innerWidth );
if( window.innerWidth > 400 ) {
console.log( "left" );
id.style.left = "200px";
id.style.bottom = 0;
id.style.top = "20px";
} else if( window.innerWidth <= 250 ) {
console.log( "left" );
id.style.left = "200px";
id.style.top = "20px";
id.style.right = 0;
}
}

Like this? Inside the position function you can write the conditions, refer the if else if condition, which checks the window size and determines the position of the element! When the document loads the position() function is ran once, to determine the initial position.
JSFiddle Demo
Javascript:
position()
window.onresize = function(event) {
position();
};
function position(){
var id = document.getElementById("img");
console.log(window.innerWidth);
if(window.innerWidth >800){
console.log("left");
id.style.left=0;
id.style.bottom=0;
id.style.top="";
}else if(window.innerWidth >600){
console.log("left");
id.style.left=0;
id.style.top=0;
id.style.right="";
}else if(window.innerWidth < 600){
console.log("right");
id.style.right=0;
id.style.top=0;
id.style.left="";
}
}

Using jquery I think you would be able to do it.
$(window).load( function() {
//find height only after all elements have loaded
var widthOfImage = $('#image').width();
//condition for image
if(widthOfImage < 200) {
$('#image').css({
'position': 'absolute',
'top': 0,
'left': 0
});
} else {
$('#image').css({
'position': 'relative',
'top': 100,
'left': 100
});
}
});

Related

If window width doesn't work on resize

I've created a function that has to run only if the window is wider than 769px. It works when the page loads, but not on resize...
It looks like this:
$(window).on('load resize', function () {
if ($(window).width() >= 769) {
...funcion...
}
});
EDITED:
Full code below
$(window).on('load resize', function () {
if ($(window).width() >= 769) {
var $element = $('#cont_quote');
var $follow = $element.find('.img_quote');
var followHeight = $element.find('.img_quote').outerHeight();
var height = $element.outerHeight() - 300;
var window_height = $(window).height();
$(window).scroll(function () {
var pos = $(window).scrollTop();
var top = $element.offset().top;
// Check if element is above or totally below viewport
if (top + height - followHeight < pos || top > pos + window_height) {
return;
}
var offset = parseInt($(window).scrollTop() - top);
if (offset > 0) {
$follow.css('transform', 'translateY('+ offset +'px)');
}
})
}
});
HTML:
<section id="cont_quote">
<article class="cont_q">
Lorem ipsum
<img class="img_quote" src="img">
</article>
</section>
Try something like this:
$(document).ready(function(){
$(window).resize(function(){
if ($(window).width() >= 769) {
...funcion...
}
}
}
You can change on ready or on load, depending on what you need, but the the function should trigger on window resize.
I think you can try this solution this is just javaScript
var onWindowResize = function(e) {
width = e.target.outerWidth;
//uncomment if need height = e.target.outerHeight;
if(width >= 769) {
//remove alert just added for debug
alert("if");
}
else{
//remove alert
alert("else");
}
}
window.addEventListener("resize", onWindowResize);

Dragging elements on a scaled div

I've tried using jquery's built in draggable and I've tried using custom drag functions with no avail. Both have their respected issues and I will try to highlight both of them.
Basically, I am trying to allow the dragging of an element that is on a scaled div container. The following methods work okay on a scaled element that is less than around 2. But if you go any higher than that, we see some issues.
Any help would be appreciated. Thank you for your time.
HTML
<div id="container">
<div id="dragme">Hi</div>
</div>
Method 1 (Jquery draggable function)
I've tried the jquery draggable function as you can see in this jsfiddle example.
The problems I found in this example are the following:
Biggest concern: The droppable container does not change when it is scaled up. So if the element is being dragged over part of the scaled container that isn't a part of it's original size, it will fail.
When you click to drag a div, it teleports a little bit away from the mouse and is not a seamless drag.
JS
var percent = 2.5;
$("#dragme").draggable({
zIndex: 3000,
appendTo: 'body',
helper: function (e, ui) {
var draggable_element = $(this),
width = draggable_element.css('width'),
height = draggable_element.css('height'),
text = draggable_element.text(),
fontsize = draggable_element.css('font-size'),
textalign = draggable_element.css('font-size');
return $('<div id="' + draggable_element.id + '" name="' + draggable_element.attr('name') + '" class="text">' + text + '</div>').css({
'position': 'absolute',
'text-align': textalign,
'background-color': "red",
'font-size': fontsize,
'line-height': height,
'width': width,
'height': height,
'transform': 'scale(' + percent + ')',
'-moz-transform': 'scale(' + percent + ')',
'-webkit-transform': 'scale(' + percent + ')',
'-ms-transform': 'scale(' + percent + ')'
});
},
start: function (e, ui) {
$(this).hide();
},
stop: function (e, ui) {
$(this).show();
}
});
$("#container").droppable({
drop: function (event, ui) {
var formBg = $(this),
x = ui.offset.left,
y = ui.offset.top,
drag_type = ui.draggable.attr('id');
var element_top = (y - formBg.offset().top - $(ui.draggable).height() * (percent - 1) / 2) / percent,
element_left = (x - formBg.offset().left - $(ui.draggable).width() * (percent - 1) / 2) / percent;
$(ui.draggable).css({
'top': element_top,
'left': element_left
});
}
});
Method 2 - Custom drag function
I've tried using a custom drag function but it unusable after around a 2 scale.
jsfiddle on a scale(2) - Looks like the draggable div is having a seizure.
jsfiddle on a scale(2.5) - The draggable div flys away when you try to drag it.
JS
(function ($) {
$.fn.drags = function (opt) {
opt = $.extend({
handle: "",
cursor: "move"
}, opt);
if (opt.handle === "") {
var $el = this;
} else {
var $parent = this;
var $el = this.find(opt.handle);
}
return $el.css('cursor', opt.cursor).on("mousedown", function (e) {
if (opt.handle === "") {
var $drag = $(this).addClass('draggable');
} else {
$(this).addClass('active-handle')
var $drag = $parent.addClass('draggable');
}
var
drg_h = $drag.outerHeight(),
drg_w = $drag.outerWidth(),
pos_y = $drag.offset().top + drg_h - e.pageY,
pos_x = $drag.offset().left + drg_w - e.pageX;
follow = function (e) {
$drag.offset({
top: e.pageY + pos_y - drg_h,
left: e.pageX + pos_x - drg_w
})
};
$(window).on("mousemove", follow).on("mouseup", function () {
$drag.removeClass('draggable');
$(window).off("mousemove", follow);
});
e.preventDefault(); // disable selection
}).on("mouseup", function () {
if (opt.handle === "") {
$(this).removeClass('draggable');
} else {
$(this).removeClass('active-handle');
$parent.removeClass('draggable');
}
});
}
})(jQuery);
$("#dragme").drags({}, function (e) {});
Here are a few of my findings to make sure dragging on a scaled container works for method one. The only caveat is to make sure you have var percent as the scaled percentage declared before any of these actions happen.
First, use this code at the top of your javascript. This wil help making sure that the droppable area works with a sacled container.
$.ui.ddmanager.prepareOffsets = function( t, event ) { var i, j, m = $.ui.ddmanager.droppables[ t.options.scope ] || [], type = event ? event.type : null, list = ( t.currentItem || t.element ).find( ":data(ui-droppable)" ).addBack(); droppablesLoop: for ( i = 0; i < m.length; i++ ) { if ( m[ i ].options.disabled || ( t && !m[ i ].accept.call( m[ i ].element[ 0 ], ( t.currentItem || t.element ) ) ) ) { continue; } for ( j = 0; j < list.length; j++ ) { if ( list[ j ] === m[ i ].element[ 0 ] ) { m[ i ].proportions().height = 0; continue droppablesLoop; }  } m[ i ].visible = m[ i ].element.css( "display" ) !== "none"; if ( !m[ i ].visible ) { continue; } if ( type === "mousedown" ) { m[ i ]._activate.call( m[ i ], event ); } m[ i ].offset = m[ i ].element.offset(); m[ i ].proportions({ width: m[ i ].element[ 0 ].offsetWidth * percent, height: m[ i ].element[ 0 ].offsetHeight * percent }); } };
Here are a few functions that are necessary to fix the drag so it works on a scaled container.
function dragFix(event, ui) { var changeLeft = ui.position.left - ui.originalPosition.left, newLeft = ui.originalPosition.left + changeLeft / percent, changeTop = ui.position.top - ui.originalPosition.top, newTop = ui.originalPosition.top + changeTop / percent; ui.position.left = newLeft; ui.position.top = newTop; }
function startFix(event, ui) { ui.position.left = 0; ui.position.top = 0;  var element = $(this); }
You will want this if you want to enable the element to be resizable on a scaled container.
function resizeFix(event, ui) { var changeWidth = ui.size.width - ui.originalSize.width, newWidth = ui.originalSize.width + changeWidth / percent, changeHeight = ui.size.height - ui.originalSize.height, newHeight = ui.originalSize.height + changeHeight / percent;  ui.size.width = newWidth; ui.size.height = newHeight; }
To make an element draggable, I use the following function.
$("ELEMENT").resizable({ minWidth: - ($(this).width()) * 10, minHeight: - ($(this).height()) * 10, resize: resizeFix, start: startFix });
$("ELEMENT").draggable({ cursor: "move", start: startFix, drag: dragFix }); }
A similar problem is mentioned here: jquery - css "transform:scale" affects '.offset()' of jquery
It seems the problem arises from the fact that jQuery fails to return exact size for scaled elements and therefore failing setting right offset values to the element.
To solve this, he is suggesting first setting scale to 1 and setting offset and then again resetting scale value.
But this alone does not solve the problem here. Since mouse position is taken while it is scaled, position values should also be divided by scale value.
Here is an edited version of code:
var scl = 2.5;
var
drg_h = $drag.outerHeight(),
drg_w = $drag.outerWidth(),
pos_y = $drag.offset().top/scl + drg_h - e.pageY/scl,
pos_x = $drag.offset().left/scl + drg_w - e.pageX/scl;
follow = function(e) {
var size = {
top:e.pageY/scl + pos_y - drg_h+scl*2,
left:e.pageX/scl + pos_x - drg_w+scl*2
};
$drag.parent().css("transform","scale(1)");
$drag.offset(size);
$drag.parent().css("transform","scale("+scl+")");
};
Note: I only replaced scale value for transform tag, since I am using chrome. You can also replace all instances or instead you can use a different class with 1 scale value.
JSFiddle is also here.
Here is an example of simple drag with scaling, however, in prue dom.
<style>
#dragme {
position:absolute;
border:1px solid red;
background:pink;
left:10px;
top:20px;
width:100px;
height:200px;
}
#container {
transform: scale(2,2) translate(100px,100px);
position:relative;
border:1px solid green;
background:grey;
width:200px;
height:300px;
}
</style>
<body>
<div id="container">
<div id="dragme">Hi</div>
</div>
<script>
var dragme=document.getElementById("dragme");
var container=document.getElementById("container");
dragme.onmousedown=function Drag(e){
this.ini_X = this.offsetLeft-e.clientX/2;
this.ini_Y = this.offsetTop-e.clientY/2;
container.onmousemove = move;
container.onmouseup = release;
return false;
}
function move(e){
e.target.style.left = e.clientX/2 + e.target.ini_X + 'px';
e.target.style.top = e.clientY/2 + e.target.ini_Y + 'px';
}
function release(){
container.onmousemove=container.onmouseup=null;
}
</script>
</body>

Animate element on scroll

I would like to animate a div when user scrolls the page.
For that, i implemented this code:
var slide = jQuery(".apresentacao-spc-01");
var opening = false;
var closing = false;
var pos = jQuery(window).scrollTop();
jQuery(window).scroll(function() {
var pos = jQuery(window).scrollTop();
console.log(pos);
if (pos > 100) {
if (!opening) {
opening = true; closing = false;
slide.stop().animate({
'opacity': 1,
'margin-left': '0px'
}, 700, function() {
opening = false;
});
}
} else {
if (!closing) {
closing = true; opening = false;
slide.stop().animate({
'opacity': 0,
'margin-left': '-1000px'
}, 500, function() {
closing = false;
});
}
}
});
The issue is:
Using "if (pos > 100) {", if the user resolution is big enough to show the element before he needs to scroll, he won't see the element unless he begins to scroll the page.
My question is:
How can I get a scroll animation that will be executed when the element is visible?
I mean: If the element is visible on page load, the animation automatically starts... If the element is not visible on page load, the animation waits the scroll reach the element to start...
Thanks.
There a few different things you could do. My first thought was to query the height of the viewport with something like this:
var viewportWidth = document.documentElement.clientWidth
, viewportHeight = document.documentElement.clientHeight
And then trigger the animation if it is taller than the distance the element is down.
A more dynamic solution would be to use a function that checks to see if the element is in viewport the automatically, that way you wouldn't need to worry about adjusting the height if you changed stuff on your page:
function isElementInViewport (el) {
var rect = el.getBoundingClientRect();
return (
rect.top >= 0 &&
rect.left >= 0 &&
rect.bottom <= (window.innerHeight || document.documentElement.clientHeight) && /*or $(window).height() */
rect.right <= (window.innerWidth || document.documentElement.clientWidth) /*or $(window).width() */
);
}
credit to this response.
There is a use guide and further information in the link provided.
Good luck!

Problems positioning element based on browser width

I have a fixed position div that I want to have position left: 0 when the browser window is smaller than 1200px, but no left positioning when larger than 1200px. I'm using this code
var $window = $(window);
function checkWidth() {
var windowsize = $window.width();
document.write(windowsize);
if (windowsize < 1200) {
document.getElementById("DBCIbox").style.left = "0";
} else {50
document.getElementById("DBCIbox").style.left = "500px";
}
}
checkWidth();
$(window).resize(checkWidth);
but it doesnt seem to be doing anything. I'm setting the left=500px as simply a test to get the javascript working, then I'll worry about where I want to position it.
I've done some googleing and from what I can tell this should work, what am I missing?
If theres a way to clear the left positioning I'd like to know that as well.
var $window = $(window);
That line is cacheing that instance of window. You need to re-evaluate $(window) everytime you call this code to get updated width and height values
Updated code below
function checkWidth() {
var $window = $(window);
var windowsize = $window.width();
document.write(windowsize);
if (windowsize < 1200) {
document.getElementById("DBCIbox").style.left = "0";
} else {50
document.getElementById("DBCIbox").style.left = "500px";
}
}
checkWidth();
$(window).resize(checkWidth);
#Jnatalzia had it right, I needed to make a few tweaks, and the comments wouldn't let me post the code, but credit goes to #Jnatalzia for the answer.
function checkWidth() {
var $window = $(window);
var windowsize = $window.width();
var position;
if (windowsize < 1390) {
document.getElementById("DBCIbox").style.marginLeft = 0 + "px";
} else if (windowsize >= 1390) {
position = windowsize - 1060;
position = position / 2;
position = position - 175;
document.getElementById("DBCIbox").style.marginLeft = position + "px";
}
}
$("document").ready(function(){
$(window).load(function(){
checkWidth();
});
$(window).resize(function(){
checkWidth();
});
});

jQuery Else / If Prevent Inheriting Styles

I am wondering how I prevent elements from retaining the same inline styles in my else / if breakpoints.
What I am doing is trying to change styling based on window width. Very much the same approach as CSS media queries, except I need to increment a numeric value, which is something I cannot do with CSS, hence the jQuery.
When I get to my final else if - where I apply an opacity to the first 5 articles - if I resize my browser back down to the less than 720px, those articles retain the opacity, which I do not want.
Any help is greatly appreciated.
$(document).ready(function() {
function checkWidth() {
var windowSize = $(window).width();
if (windowSize >= 1 && windowSize <= 479) {
var posTop = 0;
$('#main article').each(function() {
$(this).css('top', posTop + 'px');
posTop += 160;
});
} else if (windowSize >= 480 && windowSize <= 719) {
var posTop = 0;
$('#main article').each(function() {
$(this).css('top', posTop + 'px');
posTop += 240;
});
} else if (windowSize >= 720 && windowSize <= 959) {
$('#main article').slice(0, 5).each(function() {
$(this).css('opacity', 0.4);
});
}
}
// Execute on load
checkWidth();
// Bind event listener
$(window).resize(checkWidth);
});​
Add $('#main article').css('opacity', 1); at the begining of checkWidth function. By the way, you should rename this function, because what it does is not how it sounds. And there is no need in posTop variable and last each loop. My variant with some refactoring:
$(document).ready(function() {
function changeStylesDependsOnWidth() {
$('#main article').css('opacity', 1);
var windowSize = $(window).width();
if (windowSize >= 1 && windowSize <= 479) {
$('#main article').each(function(i) {
$(this).css('top', i * 160 + 'px');
});
} else if (windowSize >= 480 && windowSize <= 719) {
$('#main article').each(function(i) {
$(this).css('top', i * 240 + 'px');
});
} else if (windowSize >= 720 && windowSize <= 959) {
$('#main article').slice(0, 5).css('opacity', 0.4);
}
}
changeStylesDependsOnWidth();
$(window).resize(changeStylesDependsOnWidth);
});​

Categories

Resources